Food on airplanes tastes bland because your taste perception breaks in the air
It turns out that there’s one unpleasant part of flying that’s not the airlines’ fault, at least not directly. The food served on commercial airlines has long been famous for being bland and unappetizing, although since every snack on planes is now sold at prices that would make a movie theater blush, we might not being paying attention to this as much. Still, there’s not a lot an airline can do to make food tastier, aside from make us eat it on the ground. That’s because flying at high altitudes demands an environment that basically breaks our sense of taste. Even your favorite homemade dish would taste wrong if you ate it at 30,000 feet.
The air up there
The mechanism behind this isn’t actually flying, or being in the sky. Your taste buds aren’t somehow sensitive to altitude or anything. The issue is primarily how the air in a pressurized cabin messes with your sense of smell. Our perception of a flavor isn’t just what receptors are triggered on our tongues, as the exact ratios of different smells we experience as we chew provides a lot of information about what we’re eating. So when you’re stuffed up, food seems to have less flavor because you can’t detect those smells as well, which brings us back to airplanes.
While airplanes do pressurize their cabins so that you have enough oxygen to watch a movie at 30,000 feet in the air, they’re not recreating atmospheric conditions on the ground. The air pressure in the plane is closer to sitting on a 6,000- to 8,000-foot-tall mountain, meaning there’s less air to move yummy smells around the cabin. That air is also exceptionally dry, with less humidity that many deserts. This makes the mucus membranes in your sinuses drier, and less smells get registered by your brain, meaning you can’t detect a food’s flavor as well.
Weirdly, not all flavors are affected equally. The air pressure issues seem to knock out salt and sweet perception more than other types of flavors, such as umami. This is tough, since small amounts of salt are often used to enhance sweet flavors, and recipes have to be rethought to taste normal in flight. Further throwing things off is the fact that large amounts of salt bring out umami flavors, so just throwing salt at a bland snack may end up confusing things. On the other hand, this also explains why people tend to enjoy some foods more in the sky— tomato juice that’s got more umami is apparently preferred by lots of people that would never order a Bloody Mary on the ground.
Even if perfectly rebalanced recipes were concocted, and the air pressure optimized again to better match eating at sea levels, airplanes would still have an ambiance problem. As much as taste pivots on the balance of smells and flavors, our dining experience actually depends on nearly all our senses. Lighting has been found to influence how we perceive food, as does ambient sound. Light levels vary on planes, but the noise of the engines is usually a constant 85 decibels. All that sound further erodes our perception of salt and sugar, although it does seem to boost how well we can detect cardamom, lemon grass and curry.
Most of the above is unlikely to be addressed by airlines any time soon. Perfecting and mass-producing recipes that work better in the air, or retrofitting planes to feel more like an afternoon at the beach is obviously costly, possibly even more than $10 for a sandwich. So the next time you fly, just try to stay hydrated as much as possible, and try not to think about how much salt and sugar you might be eating without even enjoying it.
Source: Why does food taste different on planes? by Katia Moskvitch, BBC Future